Runoff and micromorphological properties of a grazed haplargid, near Cobar, NSW, Australia

Soil Research ◽  
1998 ◽  
Vol 36 (1) ◽  
pp. 87 ◽  
Author(s):  
R. S. B. Greene ◽  
W. D. Nettleton ◽  
C. J. Chartres ◽  
J. F. Leys ◽  
R. B. Cunningham
Keyword(s):  
High Intensity ◽  
Surface Soil ◽  
Soil Surface ◽  
Perennial Grasses ◽  
Total Carbon ◽  
Total Carbon Content ◽  
Land System ◽  
Goat Grazing ◽  
Intensity Grazing ◽  
Very High

We investigated the effects of 2 different grazing regimes on the surface soil properties of a dunefield land system in the semi-arid woodlands of eastern Australia. Sandy siliceous, thermic Xeric Haplargids (Siliceous Sands, Uc1·23) occur on the sandy, 2–4-m-high longitudinal dunes. Fine-loamy, siliceous, thermic Xeric Haplargids (Massive Red Earths, Uc2·13) occur in the swales between the dunes. We compared very high-intensity grazing (approx. 1 year) by feral goats with low-intensity grazing (approx. 4 years) by sheep. A rainfall simulator, applying water at the rate of 30 mm/h, measured the hydraulic properties of the surface soils formed under the 2 different grazing regimes. We examined undisturbed samples of the upper 5-cm layer of the soil surface using micromorphological techniques. In the swales, there were no differences in the effects of the 2 grazing regimes on soil properties. At low-intensity sheep grazing (0·2–0·3 sheep/ha), the soil surface on the dunes remained in an excellent condition. The surface had a good vegetative cover and consisted of either loosely packed sand grains, or areas where the sand grains were bonded together by clay and organic matter to form an organic crust. The total carbon content of the 0–2 cm depth of soil was 0·86%. Both soil surfaces have a high infiltration rate (i.e. >30 mm/h) and also appear to contain stable microaggregates of parna material distributed among the eolian sand grains. Very high-intensity goat grazing (up to 4·0 goats/ha) rapidly depleted the perennial grasses, killed most of the shrubs, and converted the soil surface on the dunes to one highly susceptible to erosion by wind. The low total carbon content (depth 0–2 cm) of 0·3% and absence of iron-stained clay coatings on the sands further support this view. The surface soil on the dunes in the very high-intensity goat-grazing plots consisted of either loosely packed sand grains or areas where poorly orientated clays coated the sand grains to form a strong, physical crust. We suggest that the physical crust may cause a change in the hydrology of the land system which may enhance the conditions for recruitment of unpalatable shrubs in the dune–swale interface. This increase in unpalatable shrubs and decrease in perennial grasses caused by the very high intensity goat grazing is therefore detrimental to the long-term productivity of these semi-arid lands.

scholarly journals The effect of crop coverage on the daily dynamism of the soil’s CO2 emission

2010 ◽  
pp. 97-102
Author(s):  
Nikolett Szőllősi ◽  
Csaba Juhász ◽  
Györgyi Kovács ◽  
József Zsembeli
Keyword(s):  
Greenhouse Gases ◽  
Co2 Emission ◽  
Soil Surface ◽  
Bare Soil ◽  
Organic Content ◽  
Total Carbon ◽  
Large Area ◽  
Total Carbon Content ◽  
Ecosystem Research ◽  
Global Carbon

Nowadays one of main goals of international ecosystem research the measurement of greenhouse gases (CO2, N2O and CH4) in different places. The fluctuation of these greenhouse gases – quantity and trend in the case of CO2 and CH4 – could be diverse with atmosphere because it depends on several effects of factors like climate, soil type, vegetation. In grassland out of the three greenhouse gases which fill a part in gas emission, in the case of CO2 soil and vegetation are the most important factors (Soussana et al., 2007).In the aspect of global carbon balance grasslands are very important by their large area extension, total carbon content, organic content store (10% of the global carbon storage) (Lemmens et al., 2006). In this summer measurements were carried out to determine CO2 emission of the soil from different soil surfaces like grass covered and bare soil surface during a whole day.

The nature of the perennial response in Mediterranean grasses. I. Water relations and summer survival in Phalaris

1968 ◽  
Vol 19 (3) ◽  
pp. 381 ◽  
Author(s):  
JR McWilliam ◽  
PJ Kramer
Keyword(s):  
Surface Soil ◽  
Perennial Grass ◽  
Soil Surface ◽  
Water Source ◽  
Perennial Grasses ◽  
Natural Conditions ◽  
Deep Roots ◽  
Surface Moisture ◽  
Summer Stress ◽  
Controlled Environments

An important factor in the survival of Phalaris tuberosa, a typical Mediterranean perennial grass, is the ability of its deep root system to supply water during the summer to the dormant culms at the soil surface. This behaviour contrasts with that of the related annual P. minor, which is unable to exploit subsoil moisture, and dies as soon as the surface moisture is exhausted. The volume of water supplied by the perennial roots is sufficient to offset transpiration losses and maintain a favourable water balance in the dormant culms during the summer stress. The importance of this water source for survival is indicated by the death of plants whenever this supply is interrupted by severing deep roots. In field soils under drought conditions roots of the perennial have been followed to a depth of 7 ft in subsoil containing available moisture. The large metaxylem vessels and heavily suberized endodermis which are a feature of these roots suggest that they are well adapted to transport water up through the dry surface soil to the base of the dormant culms. The culms also show typical xerophytic characteristics which help to minimize water loss during the summer, and maintain favourable conditions for the survival of the dormant buds which develop at the basal nodes. These conclusions concerning the survival of the perennial have been drawn from plants growing under natural conditions, and also from more detailed studies under controlled environments. They appear to be of general significance for the perennial grasses adapted to the drier Mediterranean environments and form the basis of the perennial response found in this group.

scholarly journals Study of bioremediation of water environment using constructed wetland for ecological engineering and bioenergy generation from biomass recycling

2019 ◽  
Vol 1 (1) ◽  
pp. 53-57
Author(s):  
Gotore Obey ◽  
Prattakorn Sittisom ◽  
Rameshprabu Ramaraj ◽  
Yuwalee Unpaprom ◽  
Giang Tran Van ◽  
...  
Keyword(s):  
Constructed Wetland ◽  
Water Environment ◽  
Ecological Engineering ◽  
Environmental Water ◽  
Common Reed ◽  
Surface Flow ◽  
Point Sources ◽  
Perennial Grasses ◽  
Total Carbon ◽  
Total Carbon Content

Environmental water ecosystems are facing serious hypoxia challenges because of high nutrient loadings from point and non-point sources. Therefore, the use of Vertical sub-surface flow constructed wetlands (VSSFCWs) for mitigating environmental water pollution through enhanced nitrification and denitrification processes. They offer a promising nutrient removal mechanism while also providing an ideal environment for the growth of perennial grasses. VSSFCWs not only play a role in providing safe sanitation, they produce biomass that can be harvested and used to produce fodder and biofuel in this complex global world. Biochar offers best habitation for microorganisms to decompose organic matter. The potential of constructed wetland biomass for bioenergy production through carbon sequestration had been observed. Planted with common reed macrophytes to promote biodiversity, the 0.251 m2 constructed wetland has been treating 0.03 cubic meter per day (CMD) of farm wastewater. The overall aboveground biomass was 1277 kg and total carbon content 471 kg at the peak of aboveground accumulation for the system emergent macrophyte. Incinerating of 80% biomass harvested of experimental area in an incineration plant could produce 2446 kWh for one month.

scholarly journals Change in Soil and Forest Floor Carbon after Shelterwood Harvests in a New England Oak-Hardwood Forest, USA

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Kayanna L. Warren ◽  
Mark S. Ashton
Keyword(s):  
New England ◽  
Soil Carbon ◽  
Coarse Woody Debris ◽  
Surface Soil ◽  
Woody Debris ◽  
Soil Surface ◽  
Total Carbon ◽  
Climate Mitigation ◽  
Southern New England ◽  
Significant Difference

There has been effort worldwide to quantify how much carbon forests contain in order to designate appropriate offset credits to forest carbon climate mitigation. Carbon pools on or immediately below the soil surface are understood to be very active in response to environmental change but are not well understood. Our study focused on the effects of shelterwood regeneration harvests in New England on the carbon stored in litter, woody debris, and surface soil carbon. Results demonstrate significant difference in surface (0–10 cm) soil carbon between control (nonharvested) and harvested sites, with higher carbon percentage on control sites. Results showed a significant difference in coarse woody debris with higher amounts of carbon per area on harvested sites. No significant difference in litter mass was recorded between harvested and control sites. When coarse woody debris and litter are included with soil carbon, total carbon did not have a significant decline over 20 years following shelterwood treatment to the forest to secure regeneration, but there was considerable variability among sites. When taking all surface soil carbon measurements together, our results suggest that for accounting purposes the measurement of below-ground carbon after shelterwood harvests is not necessary for the southern New England region.

Transport of soluble organic and inorganic carbon in sandy soils under nitrogen fertilization

1999 ◽  
Vol 79 (2) ◽  
pp. 303-310 ◽  
Author(s):  
F. L. Wang ◽  
A. K. Alva
Keyword(s):  
Nitrogen Fertilization ◽  
Inorganic Carbon ◽  
Average Rate ◽  
Sandy Soils ◽  
Water Soluble ◽  
Total Carbon ◽  
Total Carbon Content ◽  
Water Soluble Organic Carbon ◽  
Isobutylidene Diurea ◽  
Leaching Condition

Leaching of water soluble soil carbon plays an important role in downward transport of soil nutrients and pollutants and may be influenced by soil and management factors. We examined the leaching of water soluble carbon from two sandy soils under nitrogen fertilization by adapting an intermittent leaching-incubation technique using packed soil columns (94 × 10 cm). After 30 d, cumulative amounts of water-soluble organic carbon (SOC) leached from the Candler and Wabasso sand for various treatments in mg C column−1 were: 77 and 302 (NH4NO3), 64 and 265 (control), and 45 and 239 (isobutylidene diurea, IBDU), respectively. The IBDU and NH4NO3 treatments increased the leaching of water-soluble inorganic carbon (SIC), which ranged from 2 to 38 mg C column−1 over 30 d. At the end of eight cycles of leaching/incubation, the total carbon content increased at depth (control and NH4NO3 treatment) in the Candler sand, but decreased in the Wabasso sand. In the first leaching event, the average rate of SOC leaching from the Wabasso sand was 26 mg C column−1 d−1 which dropped rapidly to about 5 mg C column−1 d−1 towards the end of the experiment. The rate of SOC leaching from the Candler sand was much lower (<8 mg C column−1 d−1) than the rate of SOC leaching from the Wabasso sand. Compared with the unamended treatments, application of NH4NO3 increased and IBDU decreased the leaching of SOC in both soils. These effects of N application were considerable during the initial two to three leaching events only. Our results suggest that the initial rainfalls that follow a dry period may be critical for transporting SOC from the upper layer of these sandy soils. Key words: C leaching, sandy soil, intermittent leaching condition, isobutylidene

scholarly journals Characteristics of Liparis loeselii (L.) Rich. populations in selected Natura 2000 areas in eastern Poland

2020 ◽  
Vol 55 (3) ◽  
pp. 151-162
Author(s):  
Danuta Urban ◽  
Joanna Sender ◽  
Ewelina Tokarz ◽  
Andrzej Różycki
Keyword(s):  
Natura 2000 ◽  
Total Carbon ◽  
Habitat Conditions ◽  
Total Carbon Content ◽  
Poor Fen ◽  
Calcareous Fen ◽  
Liparis Loeselii ◽  
The Individual ◽  
Insight Into

AbstractIn view of the sensitivity of Liparis loeselii to changes in habitat conditions, we carried out a study with the aim to monitor population numbers, identify the individual features of the Liparis loeselii population, analyse habitat conditions, identify threats and propose conservation measures to preserve the species. The investigations were conducted in seven unmanaged objects located in three Natura 2000 areas in eastern Poland. The results of this study provide a new insight into Liparis loeselii ecology. The analysed populations inhabited some habitat types: extremely poor fen, transitional mire, rich fen, calcareous fen, spring-fed fen. The content of nutrients was similar in all the habitats. A CCA analysis revealed that the total carbon content, pH, and redox potential of the substrate determine differences between the habitats analysed. Juvenile individuals represented a maximum of 12% of the analysed populations and were the least abundant group of these plants. The flowering was primarily influenced by hydrological conditions. Based on the long-term observations reported in this article, it can be assumed that the species stands a chance of surviving at the localities analysed, provided that the habitat conditions do not change dramatically.

Improvement of the Detection Sensitivity of Edxrf Trace Element Analysis by Means of Efficient X-Ray Focusing Based on Strongly Curved Hopg Crystals

1995 ◽  
Vol 39 ◽  
pp. 109-117
Author(s):  
Burkhard Beckhoff ◽  
Birgit Kanngießer
Keyword(s):  
High Intensity ◽  
Focal Plane ◽  
Bragg Reflection ◽  
Pyrolytic Graphite ◽  
Trace Element Analysis ◽  
Detection Sensitivity ◽  
Element Analysis ◽  
X Ray ◽  
Wide Range ◽  
Very High

X-ray focusing based on Bragg reflection at curved crystals allows collection of a large solid angle of incident radiation, monochromatization of this radiation, and condensation of the beam reflected at the crystal into a small spatial cross-section in a pre-selected focal plane. Thus, for the Bragg reflected radiation, one can achieve higher intensities than for the radiation passing directly to the same small area in the focal plane. In that case one can profit considerably from X-ray focusing in an EDXRF arrangement. The 00 2 reflection at Highly Oriented Pyrolytic Graphite (HOPG) crystals offers a very high intensity of the Bragg reflected beam for a wide range of photon energies. Furthermore, curvature radii smaller than 10 mm can be achieved for HOPG crystals ensuring efficient X-ray focusing in EDXRF applications. For the trace analysis of very small amounts of specimen material deposited on small areas of thin-filter backings, HOPG based X-ray focusing may be used to achieve a very high intensity of monochromatic excitation radiation.

Fast ignition by laser driven particle beams of very high intensity

2007 ◽  
Vol 14 (7) ◽  
pp. 072701 ◽  
Author(s):  
H. Hora ◽  
J. Badziak ◽  
M. N. Read ◽  
Yu-Tong Li ◽  
Tian-Jiao Liang ◽  
...  
Keyword(s):  
High Intensity ◽  
Fast Ignition ◽  
Particle Beams ◽  
Very High
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